An important advance in the tobacco industry is the development of novel types of flavorant additives for incorporation in smoking compositions, as a consequence of the increasing demand for low delivery filter cigarettes.
Alkylpyrazines are typical of organic compounds which have been recognized as having useful properties for application as flavorants in tobacco and foodstuffs. Various species have been identified in natural products as flavorant or fragrance constituents.
Unlike alkylpyrazines which are ubiquitous in nature and heat-treated foodstuffs, acylpyrazines are more limited in their occurrence. For example, 2-acetyl-5-methylpyrazine and 2-acetyl-5-ethylpyrazine are reported as constituents of cocoa in Tabacco International, page 18ff (March 1979), and 1-(2-pyrazinyl)-1-butanone is tentatively identified as a water-soluble component of cigarette smoke in J. Agric. Food Chem., 25(2), 310 (1977).
Several acetylpyrazines are included in the F.E.M.A. listing of food additives as being useful for imparting a popcorn-nutty flavor to a foodstuff. The incorporation of acetylpyrazine, 2-acetyl-5-methylpyrazine or 2-acetyl-6-methylpyrazine as a popcorn-like flavorant in foodstuffs and tobacco is described in U.S. Pat. No. 3,402,051.
Interest in pyrazines as flavorants or fragrances has stimulated the investigation of various types of substituted pyrazines which potentially have unique organoleptic properties.
Bicyclic pyrazines are described in U.S. patents which include U.S. Pat. Nos. 3,636,177; 3,702,253; 3,748,145; 3,764,349; and 3,968,212. U.S. Pat. No. 3,705,121 discloses tricyclic pyrazine derivatives. Illustrative of polycyclic pyrazines are 5,6,7,8-tetrahydroquinoxaline and 1,2,3,4, 6,7,8,9-octahydrophenazine: ##STR2##
There is continuing research effort to develop new types of heterocyclic compounds which exhibit useful flavorant or fragrance properties.
Accordingly, it is an object of this invention to provide a novel class of acylpyrazine compounds which exhibit unique properties for application as flavorants.
It is a further object of this invention to provide smoking compositions of tobacco and non-tobacco materials containing a bicyclic acylpyrazine flavorant additive, which smoking compositions are adapted to impart flavor and aroma to mainstream and sidestream smoke under smoking conditions.
Other objects and advantages of the present invention shall become apparent from the accompanying description and disclosure.